Power supply device for LED light

Abstract

Disclosed herein is a power supply device for an LED light. The power supply device for an LED light includes a power supply unit for converting input power and providing the converted power to LEDs and a central control unit for controlling an operation of the power supply unit. The power supply unit includes a switching circuit electrically connected to both ends of the LEDs, a switching control circuit configured to control the ON/OFF of the switching circuit, and a dimming control circuit configured to control the amount of power supplied by the power supply unit in response to the ON/OFF of the switching circuit and a dimming control signal received from the central control unit, and the central control unit provides a switching control signal for controlling the switching control circuit in response to the ON/OFF of the LEDs and provides a dimming control signal for controlling the operation of the dimming control circuit.

What is claimed is: 
     
       1. A power supply device for an LED light, comprising:
 a power supply unit for converting input power and providing the converted power to LEDs; and 
 a central control unit for controlling an operation of the power supply unit, 
 wherein the power supply unit comprises: 
 a switching circuit electrically connected to both ends of the LEDs; 
 a switching control circuit configured to control an ON/OFF of the switching circuit; and 
 a dimming control circuit configured to control an amount of power supplied by the power supply unit in response to the ON/OFF of the switching circuit and a dimming control signal received from the central control unit; 
 wherein the central control unit provides a switching control signal for controlling the switching control circuit in response to the ON/OFF of the switching circuit and provides the dimming control signal for controlling an operation of the dimming control circuit, and 
 wherein when the switching circuit becomes ON, the central control unit periodically changes a size of the dimming control signal within a specific ratio or less of an LED rated voltage. 
 
     
     
       2. The power supply device of  claim 1 , wherein the power supply unit further comprises:
 a rectifier configured to convert input AC power into DC power; and 
 a converter circuit configured to control an amount of power received through the rectifier and provide the controlled power to the LEDs. 
 
     
     
       3. The power supply device of  claim 2 , wherein:
 the power supply unit further comprises a filter configured to block noise of the input AC power, and 
 the rectifier converts the AC power having the noise blocked by the filter into the DC power. 
 
     
     
       4. The power supply device of  claim 2 , wherein:
 the power supply unit further comprises a power factor compensation circuit configured to control a power factor of power received from the rectifier, and 
 the converter circuit controls the amount of the power having the power factor controlled by the power factor compensation circuit and supplies the power having the controlled power factor to the LEDs. 
 
     
     
       5. The power supply device of  claim 2 , wherein the dimming control circuit provides a signal for controlling the amount of the power to the converter circuit. 
     
     
       6. The power supply device of  claim 1 , wherein:
 when the switching circuit is turned on, the switching circuit provides the dimming control circuit with a signal proportional to an amount of a voltage at both ends of the LEDs, and 
 the dimming control circuit compares a size of a signal received from the switching circuit with a size of the dimming control signal received from the central control unit, generates a control signal based on a result of the comparison, and provides the generated control signal to the power supply unit. 
 
     
     
       7. The power supply device of  claim 1 , wherein the specific ratio is 5% of the LED rated voltage. 
     
     
       8. The power supply device of  claim 1 , wherein the switching circuit has a switching element and a resistor element connected in series. 
     
     
       9. A power supply device for an LED light, comprising:
 a power supply unit for converting input power and providing the converted power to LEDs; and 
 a central control unit for controlling an operation of the power supply unit, 
 wherein the power supply unit comprises: 
 a switching circuit electrically connected to both ends of the LEDs; 
 a switching control circuit configured to control an ON/OFF of the switching circuit; and 
 a dimming control circuit configured to control an amount of power supplied by the power supply unit in response to the ON/OFF of the switching circuit and a dimming control signal received from the central control unit; 
 wherein the central control unit provides a switching control signal for controlling the switching control circuit in response to the ON/OFF of the switching circuit and provides the dimming control signal for controlling an operation of the dimming control circuit; 
 wherein, when the switching circuit is turned on, the switching circuit provides the dimming control circuit with a signal proportional to an amount of a voltage at both ends of the LEDs, and the dimming control circuit compares a size of a signal received from the switching circuit with a size of the dimming control signal received from the central control unit, generates a control signal based on a result of the comparison, and provides the generated control signal to the power supply unit; and 
 wherein the dimming control circuit provides the power supply unit with a control signal proportional to a difference between the size of the signal received from the switching circuit and the size of the dimming control signal received from the central control unit as negative feedback.